Poseidon SE7EN User Manual
Appendix 3 Page 110
Remaining dive time (RDT)
The Remaining Dive Time (RDT) value, shown as the large number on the right side of the
Primary Display, is based on various factors, including the remaining no-decompression time
at the current depth, oxygen supply, remaining battery life, and oxygen toxicity units (OTUs).
The OTU’s will be logged and can be monitored through the PC tool. It represents the number
of minutes remaining at the current depth before one of these para meters is exceeded (“199”
is displayed if more than 199 minutes remain). When the value falls below 5 minutes, it will
flash. If a decompression ceiling is incurred, this value changes to represent the total decom-
pression time – ascent time plus decompression stop(s).
Figure 3-25.
Remaining dive time (RDT).
WARNING:
The Poseidon SE7EN rebreather is in recreational mode not
intended for use on planned decompression dives. Although
the Primary Display will provide a limited amount of information
to allow completion of safe decompression, this information is
provided ONLY as a guide when limits have been exceeded.
WARNING:
Do not allow the Remaining Dive Time to reach zero! The value
will begin to flash when several minutes remain, when an ascent
should commence. Allowing the Remaining Dive Time to reach
zero could place the diver at significant risk.
Elapsed dive time
Figure 3-26.
Elapsed dive time.
The number of minutes that have elapsed
during the dive (i.e., the total dive time) is dis-
played in the lower-right part of the Primary
Display above the RDT value. This value repre-
sents the total elapsed time since the start of
the dive. It begins incrementing only when a
dive has started, and stops incrementing when
the dive ends. If a subsequent dive is con-
ducted without allowing the unit to power-
down, then the elapsed dive time resets at next
dive start. Between the dives, the number indi-
cates time of the last dive.
Ascend/descend arrow
Located in the alarm area, is a symbol that can display an up-arrow, or a down-arrow. When the
up-arrow is displayed, the diver should immediately begin a safe, controlled ascent. The
up-arrow does not necessarily mean that the dive must be terminated – it may only indicate
that the diver is approaching the no-decompression limit at the current depth; in which case
ascending a certain amount may cause the up-arrow to stop flashing (i.e., when the depth is
shallow enough that the diver has ample remaining no-decompression time at the current
depth).
Figure 3-27.
Ascend arrow.
Figure 3-28
. Descend arrow
In the unlikely event that a diver incurs a decompression obligation (i.e., the Decompression
Ceiling Alert is displayed), and the diver then ascends above the depth at which the Decom-
pression Stop Alert is displayed, the down-arrow will flash. In this situation, simply descend
gradually until the down-arrow no longer flashes, and remain at that depth until the Decom-
pression Stop Alert no longer displays.
